• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.131-137
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• 2010

Objectives: Bisphenol A diglycidyl ether (BADGE) is a liquid compound obtained by condensation of two molecules of epichlorohydrin with one molecule of bisphenol A. General and reproductive toxicity with BADGE has been reported higher than 1000 mg/kg/day. This study was performed to show the effects of acute exposure to BADGE below 1000 mg/kg/day on the testis in adult male rats. Methods: BADGE was administered by gastric lavage in a single dose of 500, 750, 1000, and 2000 mg/kg/day in 8-week old male SPF Sprague-Dawley rats. The right testis was processed for light microscopic analysis. The left testis was homogenized and spermatids were counted to determine the daily sperm production and daily abnormal sperm production. The sperm count, sperm motility, and incidence of abnormal sperm were estimated in the epididymis. In testicular sections, the seminiferous tubules were observed for qualitative changes. The progression of spermatogenesis was arbitrarily classified as full-matured, maturing, and immature. The specimen slide was observed at 3 points and 10 seminiferous tubules were evaluated at each point. Results: The male rats exposed to single oral dose of BADGE at 750, 1000, and 2000 mg/kg/day were significantly increased the number of immature and maturing sperm on the testis. There were no significant differences with respect to sperm head count, sperm motility, and sperm abnormality in the BADGE treatment groups. Conclusions: These results suggest that single oral exposure of BADGE 750 mg/kg/day can affect adult male testis development.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.5 s.108
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• pp.451-460
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• 2006

We have designed local exposure systems for long-time mice experiments in PCS and cellular frequency band(PCS: 1,762.5 MHz, cellular: 848.5 MHz). The fabricated systems are local exposure systems of carousel type, and 40 mice can be exposed at a time. In order not to give extra stress to the mice ender experiment, the systems were fabricated to meet the environmental conditions such as illumination, ventilation, noise etc. SAR measurement was performed using a temperature probe. Measurements at 3 points in the head of mouse cadaver and solid phantom were made, and it has been confirmed that the measurement results are in good agreement with the simulation results in the real exposure environment. The exposure systems are currently used for long-term mice experiments.

• Research in Community and Public Health Nursing
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• v.22 no.1
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• pp.1-10
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• 2011

Purpose:The present study was to apply the Attitudes-Social influence-Efficacy (ASE) model in order to identify factors associated with the assertive behavior of non-smoking college students when they are exposed to secondhand smokes in Korea. Methods: Data were collected from non-smoking college students (N=1,656, 76.6% female) at two universities in Seoul and Gyeonggi-do. The main outcome measure was the assertive behavior. ASE factors such as attitudes toward being assertive, social influences, and self-efficacy as well as socio-demographic, health-related, and smoking-related factors were self-administrated. Results: The mean of the assertive behavior (range 1~5 points) was 2.23;37.6% was not at all assertive, while 4.3% was always assertive. Higher assertiveness was significantly correlated with a higher level of positive attitude, social influence and self-efficacy (p<.05 for all). Stepwise multiple regression analyses showed that the social influence was the strongest factor associated with the assertive behavior (${\beta}=0.430$, p<.001, $R^2$=.246), followed by self-efficacy, motive to assertiveness, having any family member who had diseases, and male gender. These factors explained the assertive behavior by 39.7%. Conclusion: The ASE model may explain the assertive behavior of non-smoking college students under secondhand smoke exposure. Social influence and self-efficacy were significant factors associated with their assertive behavior.

• Journal of Korean Library and Information Science Society
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• v.24
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• pp.243-274
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• 1996

The purpose of this study is to investigate the necessity, selection, organization and management of Must Books List in middle schools. A great book can change a person's life and future. Especially, reading in the juvenile period is important because of their intellectual curiosity and sensitivity. The results of the study were as follows: 1. The necessity of Must Books can be considered in two perspectives : One is the cultivation of emotion and sense of value and the other is the development of information abilities. 2. The general criteria for the selection of Must Books are whether a book is su n.0, pportive of learning activities, of extracurricular activities, and of activities for school festivals. And whether a book is contributing to the building of good characters of students or not should be considered, too. 3. The special attention should be given to such matters as the organizational and distributional ratio among subjects of the Must Books, the degree of difficulties, the ratio of books for both male and female students, the ratio of foreign books to domestics, the possibilities of further reading and the bibliographical matters. 4. The points to be duly considered for the management of Must Books List are the educational considerations, clearness of objectives, the elimination of commercialism and authoritarianism in the book selection. The Must Books List should be managed autonomously, depending on the characteristics of each school and be updated annually. However, the most important thing is that the teacher should be a good reader himself. 5. It is better to include short stories than the long one in the Must Book List. Students should be guided to read explanatory text first and then to move to the original text. And they should be exposed to books in various subjects and not to be too dependent on the Must Books List. They should be able to develop the problem solving ability through the reading of the Must Books. 6. Finally, the Must Books selection committee should be composed of both teacher librarian and subject teachers. It is desirable that books for the cultivation of emotion, for the establishment of sense of value, and for the development of information ability should be selected by consulting the various reading lists compiled by the Ministry of Education, the Board of Local Education and other authorities concerned.

• Toxicological Research
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• v.22 no.2
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• pp.95-102
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• 2006

Exposure to soluble nickel compound produces toxic effects on immune system, but the mechanism of action remains to be elucidated. Differential gene expression was studied to understand the potential molecular mechanism responsible for acute toxicity induced by nickel acetate in spleen cells. We exposed mouse spleen cells to nickel acetate with a nontoxic dose ($40{\mu}M$) and then extracted total RNA at 6 h and 12 h after exposure. The RNA was hybridized onto 10K mouse oligonucleotide microarrays, and data were analyzed using GeneSpring 7.1. Nickel had a modest effects on expression of many genes, in the range of 1.3-3 fold. The expression profile showed time-dependent changes in expression levels of differentially expressed genes, including some important genes related to cell cycle, apoptosis and DNA repair. In hierarchical cluster analysis of duplicate experiments, 111 genes were screened out. Out of these, 44 genes showing time- dependent up-regulation (>1.5 fold) and 38 genes showing down-regulation (>1.5 fold) at all time points were chosen for further analysis. The change in the expression of three genes (GPX1, GADD45B and FAIM) after nickel treatment was validated using RT-PCR. As a rule, a number of genes appear to be coordinately regulated between cell survival and cell death from nickel toxicity. In conclusion, changes in the gene profile in the spleen after nickel treatment are complex and genes with diverse functions are modulated. These findings will be contributed to the understanding of the complicated biological effects of nickel.

• Korean Journal of Community Nutrition
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• v.15 no.3
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• pp.369-378
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• 2010

School lunch programs at middle schools have increased in quantity. However, the quality of them is in fact not enough to reach the satisfactory standard, especially in the aspect of environment of school meals. It is true that there seems to be little attention to the environment. In this study, degree of satisfaction about school lunch program was surveyed for students in one middle school. Focus of survey was sanitary condition about the dining room and classroom where they have lunch. First, in order to investigate the degree of satisfaction about their dining place, questionnaire was sent out to the students at one middle school in Seoul. Questionnaire was made with reference to previous research. Second, for the study on environmental sanitation, dropping bacteria (general bacteria) is measured in three parts of dining place (entrance, serving table, dining table). Petriplate film was exposed to the responsible places for 15 minutes and then cultivated at the temperature of $32^{\circ}C$ for 48 hours before counting the number of bacteria formed. For the statistical analysis, SPSS 12.0 was used. The results of the study show that students had more satisfaction in dining room service than in classroom service. Important factors for the meal program such as "taste of food", "amount of food per student", "state of keeping warm", "appearance of food", "diversity of menu", and "kindliness of feeding staff" had more points in dining room than in classroom. For the environmental and sanitary aspect, the result of dropping bacteria (general bacteria) in dining room and classroom showed that table (5.00) and fooddistribution corner (8.67) of dining room were cleaner than those of classroom (P < 0.05). Making a good environment for school feeding will have a positive effect on the improvement of satisfaction and sanitation of school feeding. There should be expansion of dining room service for the students.

• Earthquakes and Structures
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• v.9 no.1
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• pp.49-71
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• 2015

The present paper aims at evaluating damage and collapse behavior of low-rise buildings with unidirectional mass irregularities in plan (torsional buildings). In previous earthquake events, such buildings have been exposed to extensive damages and even total collapse in some cases. To investigate the performance and collapse behavior of such buildings from probabilistic points of view, three-dimensional three and six-story reinforced concrete models with unidirectional mass eccentricities ranging from 0% to 30% and designed with modern seismic design code provisions specific to intermediate ductility class were subjected to nonlinear static as well as extensive nonlinear incremental dynamic analysis (IDA) under a set of far-field real ground motions containing 21 two-component records. Performance of each model was then examined by means of calculating conventional seismic design parameters including the response reduction (R), structural overstrength (${\Omega}$) and structural ductility (${\mu}$) factors, calculation of probability distribution of maximum inter-story drift responses in two orthogonal directions and calculation collapse margin ratio (CMR) as an indicator of performance. Results demonstrate that substantial differences exist between the behavior of regular and irregular buildings in terms of lateral load capacity and collapse margin ratio. Also, results indicate that current seismic design parameters could be non-conservative for buildings with high levels of plan eccentricity and such structures do not meet the target "life safety" performance level based on safety margin against collapse. The adverse effects of plan irregularity on collapse safety of structures are more pronounced as the number of stories increases.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.336-342
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• 2009

Avian embryos at high altitude are independent of maternal protection against hypoxia, which is contrary to mammals. It is well known that chronic hypoxic exposure at key points can significantly impact on avian development. Tibetan Chicken, a Chinese indigenous breed, living in Tibetan areas with an altitude of 2.2 to 4.1 thousand meters, has an adaptive mechanism to hypoxia. In the present study, fertilized eggs of Tibetan Chicken were incubated under 13% and 21% oxygen concentration. Two lowland chicken breeds, Shouguang Chicken, an indigenous chicken breed in Shandong Province of China, and Dwarf Recessive White Chicken, an imported breed in Beijing, were used as control groups. The embryo mass and some organs such as brain, heart, liver, stomach and eye weight in the three species were measured at Hamburger-Hamilton stage 39, 41, 43 and 45 under hypoxic and normal conditions. The results showed that in hypoxia Tibetan Chicken significantly differed from the two lowland chicken breeds in embryo mass at Hamburger-Hamilton stage 41, 43 and 45 (p<0.01). In particular, Dwarf Recessive White Chicken and Shouguang Chicken showed retarded growth in hypoxic incubation (p<0.01), whereas Tibetan Chicken showed no significant difference between hypoxic and normal conditions (p>0.05). In addition, heart and the other organs showed different susceptibility to hypoxia at the studied stages. In conclusion, chronic hypoxia induced a change in the embryo development of the three different species and Tibetan Chicken showed adaptation to hypoxia. Of note, the embryo developmental physiology of Tibetan Chicken in response to hypoxia will shed light on the process of physiological acclimation or evolutionary adaptation as well as the study of clinical disease.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.223-232
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• 2018

As the Seoul metropolitan city has the largest numbers of population and vehicles, the citizens can be exposed to hazardous air pollutants(HAPs) mainly from the vehicular exhaust and human activities. In this study, we proposed a systematic method for the selection of priority monitoring areas for HAPs using Geographic Information System (GIS). First, emission parameters(emission data, vehicle registration, monitoring data, and so on) and population parameters (population and population density) were plotted using the inverse distance weighted (IDW) interpolation. Then, the interpolation data for individual parameters, which were normalized between 1 and 5 points, were compiled for 270 grids with a resolution of $2km{\times}2km$. The total score of each grid was calculated using weights(1~5) for the individual parameters. The final ranking of each grid was assigned by four scenarios with varying fractions of the emission and population parameters from 50 : 50 to 80 : 20. Consequently, nine grids were suggested as priority monitoring areas, and all of them are located in the southwestern part of Seoul.

• Journal of Korean Library and Information Science Society
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• v.41 no.2
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• pp.27-60
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• 2010

The purpose of this study is to discuss about problems exposed as operating of bibliotherapy program and to find way to vitalize bibliotherapy as a correctional education for juvenile delinquents. The institutionalized youths of juvenile correctional school at P city which have been chosen as the sample representatives for planning, implementing, accessing and analyzing this program. The analysed results of the program show that points are to be considered: (1) Priority should be given to self-motivated youths when selecting participants. (2) Setting up as a regular program at juvenile correctional school. (3) To be necessary active participation, individual program should be provided in abreast of group program. (4) Creating adequate environment in other to ensure continuous self-healing for bibliotherapy (5) To create of professional bibliotherapy programs specialized for juvenile delinquents (6) Bases for Cooperation between the Ministry of Justice and The National Central Library, and between local juvenile corrective institutions and local libraries (7) Ultimately, To found a library at juvenile correctional schools.